Filter for removing water and/or surfactants from a lipophilic fluid

ABSTRACT

The present invention relates to processes for removing water and/or surfactants from  lipophilic fluids, absorbent materials employed in such processes, and lipophilic fluids produced by such processes.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 60/318,440 filed on Sep. 10, 2001.

FIELD OF THE INVENTION

The present invention relates to processes for removing water and/orsurfactants from lipophilic fluids, absorbent materials employed in suchprocesses, and lipophilic fluids produced by such processes.

BACKGROUND OF THE INVENTION

Lipophilic fluids, such as dry cleaning solvents, may comprise waterand/or surfactants and often times do comprise water and/or surfactantsespecially after fabric articles have been treated in dry cleaningprocesses.

The presence of water and/or surfactants in a post-fabric articletreatment lipophilic fluid is undesirable for various reasons,especially if re-use of the lipophilic fluid is desired. One reason isthat soils and/or other contaminants removed from the fabric articleduring the lipophilic fluid treatment process could become commingledand/or associated with water and/or the surfactants, thus creating apotential redeposition problem of the soils and/or contaminants onto thefabric article or new fabric articles if the lipophilic fluid is reusedprior to removing any water and/or surfactants.

Accordingly, there is a need for a process for removing and/or reducingwater and surfactants from a lipophilic fluid.

SUMMARY OF THE INVENTION

The present invention fulfills the needs described above by providingprocesses for removing water and/or surfactants from lipophilic fluids,absorbent materials employed in such processes, and lipophilic fluidsproduced by such processes.

During fabric treating processes utilizing lipophilic fluids, thelipophilic fluids typically end up containing surfactants, water and/orother “non-lipophilic fluid materials”. How the surfactants, waterand/or other “non-lipophilic fluid materials” end up in the lipophilicfluid is not the focus of the present invention, rather the presentinvention focuses on removing and/or reducing water and/or thesurfactants from the lipophilic fluids such that the lipophilic fluidsare pure or substantially pure. In other words, such that the pureand/or substantially pure lipophilic fluids preferably comprise a levelof water and the surfactants that does not impair the performance of thepure and/or substantially pure lipophilic fluid in subsequent steps ofand/or new fabric treating processes. Preferably, the level of waterand/or the surfactants present in the pure or substantially purelipophilic fluid is less than about 1%, and/or from about 0% to about 1%and/or from about 0% to about 0.5% and/or from about 0% to about 0.3%and/or from about 0.00001% to about 0.1% and/or from about 0.0001% toabout 0.01% by weight of the lipophilic fluid. In one embodiment, thelevel of water and/or surfactants present in a pure or substantiallypure lipophilic fluid is less than 5 ppm.

The present invention provides methods and systems for safely separatingwater and/or surfactants from a lipophilic fluid, preferably in a costeffective, efficient, and safe manner.

In a first embodiment, the present invention provides a process forremoving water and/or surfactants from an emulsion of a lipophilic fluidand water and/or surfactant, said process comprising the step ofexposing said emulsion to an absorbent matrix comprising an absorbentmaterial in order to effect the removal of said water and/or saidsurfactants from said emulsion of a lipophilic fluid and water and/orsurfactant. The lipophilic fluid is recovered from the absorbent matrixas pure or substantially pure lipophilic fluid.

In a second embodiment, the present invention provides a system forremoving water and/or surfactants from an emulsion of a lipophilic fluidand water and/or surfactant, said system comprising exposing saidemulsion to an absorbent matrix comprising an absorbent material inorder to effect the removal of said water and/or surfactants from saidemulsion of a lipophilic fluid and water and/or surfactant. Thelipophilic fluid is recovered from the absorbent matrix as a pure orsubstantially pure lipophilic fluid.

In a third embodiment, the present invention provides a compositioncomprising an absorbent material, lipophilic fluid, water and anemulsifier. The emulsifier may be a surfactant.

In a fourth embodiment, the present invention provides a compositioncomprising an absorbent material, lipophilic fluid and a surfactant.

In a fifth embodiment, the present invention provides a compositioncomprising an absorbent material, lipophilic fluid, water and asurfactant.

In yet another embodiment, the present invention provides a filtercomprising the absorbent material of the present invention.

These and other aspects, features and advantages will become apparent tothose of ordinary skill in the art from the following detaileddescription and the appended claims. All percentages, ratios andproportions herein are by weight, unless otherwise specified. Alltemperatures are in degrees Celsius (° C.) unless otherwise specified.All measurements are in SI units unless otherwise specified. Alldocuments cited are, in relevant part, incorporated herein by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of an absorbent material for usewith the processes of the present invention.

DETAILED DESCRIPTION Definitions

The term “fabric article” used herein is intended to mean any articlethat is customarily cleaned in a conventional laundry process or in adry cleaning process. As such the term encompasses articles of clothing,linen, drapery, and clothing accessories. The term also encompassesother items made in whole or in part of fabric, such as tote bags,furniture covers, tarpaulins and the like.

The term “absorbent material” or “absorbent polymer” used herein isintended to mean any material capable of selectively absorbing oradsorbing water and/or water-containing liquids without absorbinglipophilic fluids as described in detail. In other words, absorbentmaterials or absorbent polymers comprise a water absorbing agent. In theart they may also be referred to as “responsive gels,” “gel,” and“polymeric gel.” For a list of phase changing gels, see the textbookResponsive Gels, Volume Transitions II, Ed K. Dusek, Springer VerlagBerlin, 1993 (herein incorporated by reference). See also,Thermo-responsive Gels, Radiat. Phys. Chem., Volume 46, No. 2, pp.185-190, Elsevier Science Ltd. Great Britain, 1995 (herein incorporatedby reference). Super absorbent polymers, also suitable for use with thepresent invention, are polymeric materials that have an absorptioncapacity at or above 5 grams/gram. See also, Superabsorbent PolymersScience and Technology, edited by Fredric L. Buchholz and Nicholas A.Peppas, American Chemical Society, Washington D.C., 1994 (particularlyChapter 9 by Tadao Shimomura and Takashi Namba entitled “Preparation andApplication of High-Performance Superabsorbent Polymers) hereinincorporated by reference.

The water absorbing agent of the present invention may have a waterabsorbing capacity of at least about 50 g water/g of water absorbingagent and/or from about 50 g water/g of water absorbing agent to about300 g water/g water absorbing agent and/or from about 100 g of water/gof water absorbing agent to about 200 g of water/g of water absorbingagent. The water absorbing capacity of the water absorbing agent isdetermined in a water environment, not a lipophilic fluid environment.

The water absorbing agent may have an average particle size of at leastabout 5 micons and/or from about 5 microns to about 500 microns and/orfrom about 50 microns to about 350 microns.

The absorbent material of the present invention may comprise two or morewater absorbing agents 1) each separate and discrete from each other or2) commingled with one another.

The term “absorbent matrix permeability aid” or “spacer material” or“spacer” used herein is intended to mean any fibrous or particulatematerial that is, at most, only slightly soluble in water and/orlipophilic fluid.

The term “absorbent matrix” used herein is intended to mean a matrix inany form that is capable of absorbing and/or adsorbing water. Atminimum, it comprises an absorbent material. It may optionally comprisea spacer material and/or a high surface area material.

The term “lipophilic fluid” used herein is intended to mean anynonaqueous fluid capable of removing sebum, as described in more detailherein below.

The term “cleaning composition” and/or “treating composition” usedherein is intended to mean any lipophilic fluid-containing compositionthat comes into direct contact with fabric articles to be cleaned. Itshould be understood that the term encompasses uses other than cleaning,such as conditioning and sizing. Furthermore, optional cleaning adjunctssuch as additional surfactants other than those surfactants describedabove, bleaches, and the like may be added to the “cleaningcomposition”. That is, cleaning adjuncts may be optionally combined withthe lipophilic fluid. These optional cleaning adjuncts are described inmore detail herein below. Such cleaning adjuncts may be present in thecleaning compositions of the present invention at a level of from 0.01%to about 10% by weight of the cleaning composition.

The term “soil” means any undesirable substance on a fabric article thatis desired to be removed. By the terms “water-based” or “hydrophilic”soils, it is meant that the soil comprised water at the time it firstcame in contact with the fabric article, or the soil retains asignificant portion of water on the fabric article. Examples ofwater-based soils include, but are not limited to beverages, many foodsoils, water soluble dyes, bodily fluids such as sweat, urine or blood,outdoor soils such as grass stains and mud.

The term “capable of suspending water in a lipophilic fluid” means thata material is able to suspend, solvate or emulsify water, which isimmiscible with the lipophilic fluid, in a way that the water remainsvisibly suspended, solvated or emulsified when left undisturbed for aperiod of at least five minutes after initial mixing of the components.In some examples of compositions in accordance with the presentinvention, the compositions may be colloidal in nature and/or appearmilky. In other examples of compositions in accordance with the presentinvention, the compositions may be transparent.

The term “insoluble in a lipophilic fluid” means that when added to alipophilic fluid, a material physically separates from the lipophilicfluid (i.e. settle-out, flocculate, float) within 5 minutes afteraddition, whereas a material that is “soluble in a lipophilic fluid”does not physically separate from the lipophilic fluid within 5 minutesafter addition.

The term “consumable detergent composition” means any composition, thatwhen combined with a lipophilic fluid, results in a cleaning compositionaccording to the present invention.

The term “processing aid” refers to any material that renders theconsumable detergent composition more suitable for formulation,stability, and/or dilution with a lipophilic fluid to form a cleaningcomposition in accordance with the present invention.

The term “mixing” as used herein means combining two or more materials(i.e., fluids, more specifically a lipophilic fluid and a consumabledetergent composition) in such a way that a homogeneous mixture isformed. Suitable mixing processes are known in the art. Nonlimitingexamples of suitable mixing processes include vortex mixing processesand static mixing processes.

Filter

The filter of the present invention comprises an absorbent material inaccordance with the present invention. The filter may have a housingwithin which the absorbent material is housed. The housing may have aninlet through which the emulsion of lipophilic fluid and water and/orsurfactant flow through to contact the absorbent material.

Lipophilic Fluid

The lipophilic fluid herein is one having a liquid phase present underoperating conditions of a fabric article treating appliance, in otherwords, during treatment of a fabric article in accordance with thepresent invention. In general such a lipophilic fluid can be fullyliquid at ambient temperature and pressure, can be an easily meltedsolid, e.g., one which becomes liquid at temperatures in the range fromabout 0 deg. C to about 60 deg. C, or can comprise a mixture of liquidand vapor phases at ambient temperatures and pressures, e.g., at 25 deg.C and 1 atm. pressure. Thus, the lipophilic fluid is not a compressiblegas such as carbon dioxide.

It is preferred that the lipophilic fluids herein be nonflammable orhave relatively high flash points and/or low VOC (volatile organiccompound) characteristics, these terms having their conventionalmeanings as used in the dry cleaning industry, to equal or, preferably,exceed the characteristics of known conventional dry cleaning fluids.

Moreover, suitable lipophilic fluids herein are readily flowable andnonviscous.

In general, lipophilic fluids herein are required to be fluids capableof at least partially dissolving sebum or body soil as defined in thetest hereinafter. Mixtures of lipophilic fluid are also suitable, andprovided that the requirements of the Lipophilic Fluid Test, asdescribed below, are met, the lipophilic fluid can include any fractionof dry-cleaning solvents, especially newer types including fluorinatedsolvents, or perfluorinated amines. Some perfluorinated amines such asperfluorotributylamines while unsuitable for use as lipophilic fluid maybe present as one of many possible adjuncts present in the lipophilicfluid-containing composition.

Other suitable lipophilic fluids include, but are not limited to, diolsolvent systems e.g., higher diols such as C6- or C8- or higher diols,organosilicone solvents including both cyclic and acyclic types, and thelike, and mixtures thereof.

A preferred group of nonaqueous lipophilic fluids suitable forincorporation as a major component of the compositions of the presentinvention include low-volatility nonfluorinated organics, silicones,especially those other than amino functional silicones, and mixturesthereof. Low volatility nonfluorinated organics include for exampleOLEAN® and other polyol esters, or certain relatively nonvolatilebiodegradable mid-chain branched petroleum fractions.

Another preferred group of nonaqueous lipophilic fluids suitable forincorporation as a major component of the compositions of the presentinvention include, but are not limited to, glycol ethers, for examplepropylene glycol methyl ether, propylene glycol n-propyl ether,propylene glycol t-butyl ether, propylene glycol n-butyl ether,dipropylene glycol methyl ether, dipropylene glycol n-propyl ether,dipropylene glycol t-butyl ether, dipropylene glycol n-butyl ether,tripropylene glycol methyl ether, tripropylene glycol n-propyl ether,tripropylene glycol t-butyl ether, tripropylene glycol n-butyl ether.Suitable silicones for use as a major component, e.g., more than 50%, ofthe composition include cyclopentasiloxanes, sometimes termed “D5”,and/or linear analogs having approximately similar volatility,optionally complemented by other compatible silicones. Suitablesilicones are well known in the literature, see, for example, KirkOthmer's Encyclopedia of Chemical Technology, and are available from anumber of commercial sources, including General Electric, ToshibaSilicone, Bayer, and Dow Corning. Other suitable lipophilic fluids arecommercially available from Procter & Gamble or from Dow Chemical andother suppliers.

Qualification of Lipophilic Fluid and Lipophilic Fluid Test (LF Test)

Any nonaqueous fluid that is both capable of meeting known requirementsfor a dry-cleaning fluid (e.g, flash point etc.) and is capable of atleast partially dissolving sebum, as indicated by the test methoddescribed below, is suitable as a lipophilic fluid herein. As a generalguideline, perfluorobutylamine (Fluorinert FC-43®) on its own (with orwithout adjuncts) is a reference material which by definition isunsuitable as a lipophilic fluid for use herein (it is essentially anonsolvent) while cyclopentasiloxanes have suitable sebum-dissolvingproperties and dissolves sebum.

The following is the method for investigating and qualifying othermaterials, e.g., other low-viscosity, free-flowing silicones, for use asthe lipophilic fluid. The method uses commercially available Crisco®canola oil, oleic acid (95% pure, available from Sigma Aldrich Co.) andsqualene (99% pure, available from J. T. Baker) as model soils forsebum. The test materials should be substantially anhydrous and freefrom any added adjuncts, or other materials during evaluation.

Prepare three vials, each vial will contain one type of lipophilic soil.Place 1.0 g of canola oil in the first; in a second vial place 1.0 g ofthe oleic acid (95%), and in a third and final vial place 1.0 g of thesqualene (99.9%). To each vial add 1 g of the fluid to be tested forlipophilicity. Separately mix at room temperature and pressure each vialcontaining the lipophilic soil and the fluid to be tested for 20 secondson a standard vortex mixer at maximum setting. Place vials on the benchand allow to settle for 15 minutes at room temperature and pressure. If,upon standing, a clear single phase is formed in any of the vialscontaining lipophilic soils, then the nonaqueous fluid qualifies assuitable for use as a “lipophilic fluid” in accordance with the presentinvention. However, if two or more separate layers are formed in allthree vials, then the amount of nonaqueous fluid dissolved in the oilphase will need to be further determined before rejecting or acceptingthe nonaqueous fluid as qualified.

In such a case, with a syringe, carefully extract a 200-microlitersample from each layer in each vial. The syringe-extracted layer samplesare placed in GC auto sampler vials and subjected to conventional GCanalysis after determining the retention time of calibration samples ofeach of the three models soils and the fluid being tested. If more than1% of the test fluid by GC, preferably greater, is found to be presentin any one of the layers which consists of the oleic acid, canola oil orsqualene layer, then the test fluid is also qualified for use as alipophilic fluid. If needed, the method can be further calibrated usingheptacosafluorotributylamine, i.e., Fluorinert FC-43 (fail) andcyclopentasiloxane (pass). A suitable GC is a Hewlett Packard GasChromatograph HP5890 Series II equipped with a split/splitless injectorand FID. A suitable column used in determining the amount of lipophilicfluid present is a J&W Scientific capillary column DB-1HT, 30 meter,0.25 mm id, 0.1 um film thickness cat#1221131. The GC is suitablyoperated under the following conditions:

Carrier Gas: Hydrogen

Column Head Pressure: 9 psi

Flows: Column Flow @˜1.5 ml/min.

-   -   Split Vent @˜250-500 ml/min.    -   Septum Purge @1 ml/min.

Injection: HP 7673 Autosampler, 10 ul syringe, 1 ul injection

Injector Temperature: 350° C.

Detector Temperature: 380° C.

Oven Temperature Program: initial 60° C. hold 1 min.

-   -   rate 25° C./min.    -   final 380° C. hold 30 min.

Preferred lipophilic fluids suitable for use herein can further bequalified for use on the basis of having an excellent garment careprofile. Garment care profile testing is well known in the art andinvolves testing a fluid to be qualified using a wide range of garmentor fabric article components, including fabrics, threads and elasticsused in seams, etc., and a range of buttons. Preferred lipophilic fluidsfor use herein have an excellent garment care profile, for example theyhave a good shrinkage and/or fabric puckering profile and do notappreciably damage plastic buttons. Certain materials which in sebumremoval qualify for use as lipophilic fluids, for example ethyl lactate,can be quite objectionable in their tendency to dissolve buttons, and ifsuch a material is to be used in the compositions of the presentinvention, it will be formulated with water and/or other solvents suchthat the overall mix is not substantially damaging to buttons. Otherlipophilic fluids, D5, for example, meet the garment care requirementsquite admirably. Some suitable lipophilic fluids may be found in grantedU.S. Pat. Nos. 5,865,852; 5,942,007; 6,042,617; 6,042,618; 6,056,789;6,059,845; and 6,063,135, which are incorporated herein by reference.

Lipophilic fluids can include linear and cyclic polysiloxanes,hydrocarbons and chlorinated hydrocarbons, with the exception of PERCand DF2000 which are explicitly not covered by the lipophilic fluiddefinition as used herein. More preferred are the linear and cyclicpolysiloxanes and hydrocarbons of the glycol ether, acetate ester,lactate ester families. Preferred lipophilic fluids include cyclicsiloxanes having a boiling point at 760 mm Hg. of below about 250° C.Specifically preferred cyclic siloxanes for use in this invention areoctamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, anddodecamethylcyclohexasiloxane. Preferably, the cyclic siloxane comprisesdecamethylcyclopentasiloxane (D5, pentamer) and is substantially free ofoctamethylcyclotetrasiloxane (tetramer) anddodecamethylcyclohexasiloxane (hexamer).

However, it should be understood that useful cyclic siloxane mixturesmight contain, in addition to the preferred cyclic siloxanes, minoramounts of other cyclic siloxanes including octamethylcyclotetrasiloxaneand hexamethylcyclotrisiloxane or higher cyclics such astetradecamethylcycloheptasiloxane. Generally the amount of these othercyclic siloxanes in useful cyclic siloxane mixtures will be less thanabout 10 percent based on the total weight of the mixture. The industrystandard for cyclic siloxane mixtures is that such mixtures compriseless than about 1% by weight of the mixture ofoctamethylcyclotetrasiloxane.

Accordingly, the lipophilic fluid of the present invention preferablycomprises more than about 50%, more preferably more than about 75%, evenmore preferably at least about 90%, most preferably at least about 95%by weight of the lipophilic fluid of decamethylcyclopentasiloxane.Alternatively, the lipophilic fluid may comprise siloxanes which are amixture of cyclic siloxanes having more than about 50%, preferably morethan about 75%, more preferably at least about 90%, most preferably atleast about 95% up to about 100% by weight of the mixture ofdecamethylcyclopentasiloxane and less than about 10%, preferably lessthan about 5%, more preferably less than about 2%, even more preferablyless than about 1%, most preferably less than about 0.5% to about 0% byweight of the mixture of octamethylcyclotetrasiloxane and/ordodecamethylcyclohexasiloxane.

The level of lipophilic fluid, when present in the fabric articletreating compositions according to the present invention, is preferablyfrom about 70% to about 99.99%, more preferably from about 90% to about99.9%, and even more preferably from about 95% to about 99.8% by weightof the fabric article treating composition.

The level of lipophilic fluid, when present in the consumable detergentcompositions according to the present invention, is preferably fromabout 0.1% to about 90%, more preferably from about 0.5% to about 75%,and even more preferably from about 1% to about 50% by weight of theconsumable detergent composition.

Lipophilic Fluid Adjuncts

During fabric treating processes utilizing lipophilic fluids, thelipophilic fluids typically end up containing surfactant componentsand/or surfactants, water and/or other “non-lipophilic fluid materials”.

Surfactant Component

Surfactant components and/or conventional surfactants may become mixedwith the lipophilic fluid as a result of a fabric treating processutilizing both materials or may be added to a lipophilic fluid prior tousing the lipophilic fluid for a fabric treating process. How thesurfactant component and/or conventional surfactant comes to be presentin the lipophilic fluid is not particularly important for the presentinvention. This present invention addresses the problem of removing thesurfactant component and/or conventional surfactants from the lipophilicfluid.

Surfactant components (i.e., materials that have properties similar tosurfactants) and conventional surfactants that may be present in thesurfactant-containing lipophilic fluid of the present invention.

A wide range of conventional surfactants can be used as treating agentsin the treating compositions of the present invention.

Nonlimiting examples of these other surfactants include conventionalanionic, nonionic, cationic and zwitterionic surfactants.

Surfactants included in the treating compositions afforded by thepresent invention comprise at least 0.01%, preferably at least about0.1%, more preferably at least about 0.5%, even more preferably at leastabout 1%, most preferably at least about 3% to about 80%, morepreferably to about 60%, most preferably to about 50% by weight ofcomposition depending upon the particular surfactants used and thedesired effects to be achieved.

The surfactant can be nonionic, anionic, amphoteric, amphophilic,zwitterionic, cationic, semi-polar nonionic, and mixtures thereof,nonlimiting examples of which are disclosed in U.S. Pat. Nos. 5,707,950and 5,576,282. A typical listing of anionic, nonionic, amphoteric andzwitterionic classes, and species of these surfactants, is given in U.S.Pat. No. 3,664,961 issued to Norris on May 23, 1972. Preferredcompositions comprise nonionic surfactants and/or mixtures of nonionicsurfactants with other surfactants, especially anionic surfactants.

Nonlimiting examples of surfactants useful herein include theconventional C₈-C₁₈ alkyl ethoxylates (“AE”), with EO about 1-22,including the so-called narrow peaked alkyl ethoxylates and C₆-C₁₂ alkylphenol alkoxylates (especially ethoxylates and mixed ethoxy/propoxy),alkyl dialkyl amine oxide, alkanoyl glucose amide, C₁₁-C₁₈ alkyl benzenesulfonates and primary, secondary and random alkyl sulfates, the C₁₀-C₁₈alkyl alkoxy sulfates, the C₁₀-C₁₈ alkyl polyglycosides and theircorresponding sulfated polyglycosides, C₁₂-C₁₈ alpha-sulfonated fattyacid esters, C₁₂-C₁₈ alkyl and alkyl phenol alkoxylates (especiallyethoxylates and mixed ethoxy/propoxy), C₁₂-C₁₈ betaines, schercotainesand sulfobetaines (“sultaines”), C₁₀-C₁₈ amine oxides, and the like.Other conventional useful surfactants are listed in standard texts.

The surfactant components and/or surfactants may include the followingnonlimiting examples:

-   -   a) Anionic surfactants (e.g., alkyl or aryl sulfates, aerosol        derivatives, etc)    -   b) Cationic or basic surfactants (e.g., quaternary surfactants,        primary and secondary amines, etc.)    -   c) Non-ionic surfactants (e.g., Brij surfactants, Neodol        surfactants, etc.)

The surfactant component of the present invention is a material that iscapable of suspending water in a lipophilic fluid and enhancing soilremoval benefits of a lipophilic fluid. As a condition of theirperformance, said materials are soluble in the lipophilic fluid.

One class of materials can include siloxane-based surfactants(siloxane-based materials). The siloxane-based surfactants in thisapplication may be siloxane polymers for other applications. Thesiloxane-based surfactants typically have a weight average molecularweight from 500 to 20,000. Such materials, derived frompoly(dimethylsiloxane), are well known in the art. In the presentinvention, not all such siloxane-based surfactants are suitable, becausethey do not provide improved cleaning of soils compared to the level ofcleaning provided by the lipophilic fluid itself.

Suitable siloxane-based surfactants comprise a polyether siloxane havingthe formula:M_(a)D_(b)D′_(c)D″_(d)M′_(2-a)wherein a is 0-2; b is 0-1000; c is 0-50; d is 0-50, provided that a+c+dis at least 1;

M is R¹ _(3-e)X_(e)SiO_(1/2) wherein R¹ is independently H, or amonovalent hydrocarbon group, X is hydroxyl group, and e is 0 or 1;

M′ is R² ₃SiO_(1/2) wherein R² is independently H, a monovalenthydrocarbon group, or(CH₂)_(f)—(C6H4)_(g)O—(C₂H₄O)_(h)—(C₃H₆O)_(i)—(C_(k)H_(2k)O)_(j)—R³,provided that at least one R² is (CH₂)_(f)—(C6H4)_(g)O—(C₂H₄O)_(h)—(C₃H₆O)_(i)—(C_(k)H_(2k)O)_(j)—R³, wherein R³ isindependently H, a monovalent hydrocarbon group or an alkoxy group, f is1-10, g is 0 or 1, h is 1-50, i is 0-50, j is 0-50, k is 4-8;

D is R⁴ ₂SiO_(2/2) wherein R⁴ is independently H or a monovalenthydrocarbon group;

D′ is R⁵ ₂SiO_(2/2) wherein R⁵ is independently R² provided that atleast one R⁵ is (CH₂)_(f)—(C6H4)_(g)O—(C₂H₄O)_(h)—(C₃H₆O)_(i)—(C_(k)H_(2k)O)_(j)—R³, wherein R³ isindependently H, a monovalent hydrocarbon group or an alkoxy group, f is1-10, g is 0 or 1, h is 1-50, i is 0-50, j is 0-50, k is 4-8; and

D″ is R⁶ ₂SiO_(2/2) wherein R⁶ is independently H, a monovalenthydrocarbon group or(CH₂)_(l)(C₆H₄)_(m)(A)_(n)-[(L)_(o)-(A′)_(p)-]_(q)-(L′)_(r)Z(G)_(s),wherein l is 1-10; m is 0 or 1; n is 0-5; o is 0-3; p is 0 or 1; q is0-10; r is 0-3; s is 0-3; C₆H₄ is unsubstituted or substituted with aC₁₋₁₀ alkyl or alkenyl; A and A′ are each independently a linking moietyrepresenting an ester, a keto, an ether, a thio, an amido, an amino, aC₁₋₄ fluoroalkyl, a C₁₋₄ fluoroalkenyl, a branched or straight chainedpolyalkylene oxide, a phosphate, a sulfonyl, a sulfate, an ammonium, andmixtures thereof; L and L′ are each independently a C₁₋₃₀ straightchained or branched alkyl or alkenyl or an aryl which is unsubstitutedor substituted; Z is a hydrogen, carboxylic acid, a hydroxy, aphosphato, a phosphate ester, a sulfonyl, a sulfonate, a sulfate, abranched or straight-chained polyalkylene oxide, a nitryl, a glyceryl,an aryl unsubstituted or substituted with a C₁₋₃₀alkyl or alkenyl, acarbohydrate unsubstituted or substituted with a C₁₋₁₀alkyl or alkenylor an ammonium; G is an anion or cation such as H⁺, Na⁺, Li⁺, K⁺, NH₄ ⁺,Ca⁺², Mg⁺², Cl⁻, Br⁻, I⁻, mesylate or tosylate.

Examples of the types of siloxane-based surfactants described hereinabove may be found in EP-1,043,443A1, EP-1,041,189 and WO-01/34,706 (allto GE Silicones) and U.S. Pat. No. 5,676,705, U.S. Pat. No. 5,683,977,U.S. Pat. No. 5,683,473, and EP-1,092,803A1 (all to Lever Brothers).

Nonlimiting commercially available examples of suitable siloxane-basedsurfactants are TSF 4446 (ex. General Electric Silicones), XS69-B5476(ex. General Electric Silicones); Jenamine HSX (ex. DelCon) and Y12147(ex. OSi Specialties).

A second preferred class of materials suitable for the surfactantcomponent is organic in nature. Preferred materials areorganosulfosuccinate surfactants, with carbon chains of from about 6 toabout 20 carbon atoms. Most preferred are organosulfosuccinatescontaining dialkly chains, each with carbon chains of from about 6 toabout 20 carbon atoms. Also preferred are chains containing aryl oralkyl aryl, substituted or unsubstituted, branched or linear, saturatedor unsaturated groups.

Nonlimiting commercially available examples of suitableorganosulfosuccinate surfactants are available under the trade names ofAerosol OT and Aerosol TR-70 (ex. Cytec).

In one embodiment, the treating agent is insoluble in water. In anotherembodiment, the treating agent is insoluble in water, but soluble in alipophilic fluid. In yet another embodiment, the treating agent isinsoluble in water, soluble in a lipophilic fluid and has an HLB of fromabout 1 to about 9 or from about 1 to about 7 or from about 1 to about5.

In still another embodiment, the treating agent is insoluble in waterand insoluble in a lipophilic fluid. In still yet another embodiment,the treating agent in conjunction with a solubilizing agent is at leastpartially soluble in a lipophilic fluid and/or water. In thesolubilizing agent embodiment, the treating agent is present at a levelin the treating composition at from about 0.001% to about 5% or fromabout 0.001% to about 3% or from about 0.001% to about 1% by weight ofthe treating composition.

Nonlimiting examples of suitable treating agents include treating agentscommercially available from Dow Corning under tradenames such as DC1248,SF1528 DC5225C and DCQ4 3667; and Silwets from Witco under tradenamessuch as L8620, L7210, L7220.

The surfactant component, when present in the surfactant-containinglipophilic fluid can be present at any level, typically the surfactantcomponent is present at a level of from about 0.01% to about 10%, morepreferably from about 0.02% to about 5%, even more preferably from about0.05% to about 2% by weight of the cleaning composition.

Another surfactant component/surfactant that may be present in thesurfactant-containing lipophilic fluid is characterized as non-siliconeadditives. The non-silicone additives preferably comprise a stronglypolar and/or hydrogen-bonding head group. Examples of the strongly polarand/or hydrogen-bonding head group are alcohols, carboxylic acids,sulfates, sulphonates, phosphates, phosphonates, and nitrogen containingmaterials. Preferred non-silicone additives are nitrogen containingmaterials selected from the group consisting of primary, secondary andtertiary amines, diamines, triamines, ethoxylated amines, amine oxides,amides, betaines, quaternary ammonium salts, and mixtures thereof.Alkylamines are particularly preferred. Additionally, branching on thealkyl chain to help lower the melting point is highly preferred. Evenmore preferred are primary alkylamines comprising from about 6 to about22 carbon atoms.

Particularly preferred primary alkylamines are oleylamine (commerciallyavailable from Akzo under the trade name Armeen OLD), dodecylamine(commercially available from Akzo under the trade name Armeen 12D),branched C₁₆-C₂₂ alkylamine (commercially available from Rohm & Haasunder the trade name Primene JM-T) and mixtures thereof.

The non-silicone additives, when present in the treating compositions ofthe present invention, preferably comprises from about 0.01% to about10%, more preferably from about 0.02% to about 5%, even more preferablyfrom about 0.05% to about 2% by weight of the treating composition.

Polar Solvent

The contaminant-containing lipophilic fluid of the present invention maycomprise a polar solvent. Non-limiting examples of polar solventsinclude: water, alcohols, glycols, polyglycols, ethers, carbonates,dibasic esters, ketones, other oxygenated solvents, and mixuturesthereof. Further examples of alcohols include: C1-C126 alcohols, such aspropanol, ethanol, isopropyl alcohol, etc. . . . , benzyl alcohol, anddiols such as 1,2-hexanediol. The Dowanol series by Dow Chemical areexamples of glycols and polyglycols useful in the present invention,such as Dowanol TPM, TPnP, DPnB, DPnP, TPnB, PPh, DPM, DPMA, DB, andothers. Further examples include propylene glycol, butylene glycol,polybutylene glycol and more hydrophobic glycols. Examples of carbonatesolvents are ethylene, propylene and butylene carbonantes such as thoseavailable under the Jeffsol tradename. Polar solvents for the presentinvention can be further identified through their dispersive (□_(D)),polar (□_(P)) and hydrogen bonding (□_(H)) Hansen solubility parameters.Preferred polar solvents or polar solvent mixtures have fractional polar(f_(P)) and fractional hydrogen bonding (f_(H)) values of f_(P)>0.02 andf_(H)>0.10, where f_(p)=□_(P)/(□_(D)+□_(P)+□_(H)) andf_(H)=□_(H)/(□_(D)+□_(P)+□_(H)), more preferably f_(P)>0.05 andf_(H)>0.20, and most preferably f_(P)>0.07 and f_(H)>0.30.

Polar solvent may be present in the contaminant-containing lipophilicfluid at any level, typically it is present in thecontaminant-containing lipophilic fluid at a level of from about 0.001%to about 10%, more preferably from about 0.005% to about 5%, even morepreferably from about 0.01% to about 1% by weight of thecontaminant-containing lipophilic fluid.

In one embodiment, the contaminant-containing lipophilic fluid comprisesfrom about 0% to about 5% or from about 0% to about 3% or from about0.0001% to about 1% by weight of the contaminant-containing lipophilicfluid of a polar solvent.

In the treating composition of the present invention, the levels ofpolar solvent can be from about 0 to about 70%, preferably 1 to 50%,even more preferably 1 to 30% by weight of the detergent composition.

In another embodiment, the surfactant-containing lipophilic fluidcomprises a surfactant selected from the group consisting of anionicsurfactants, cationic surfactants, nonionic surfactants, zwitterionicsurfactants and mixtures thereof.

Absorbent Materials

The absorbent materials of the present invention comprise one or morewater absorbing agents. Suitable water absorbing agents and/or absorbentmaterials comprising water absorbing agents of the present invention aredescribed herein below.

Hydrogel-Forming Absorbent Polymers

The absorbent polymers of the present invention preferably comprise atleast one hydrogel-forming absorbent polymer (also referred to ashydrogel-forming polymer). Hydrogel-forming polymers useful in thepresent invention include a variety of water-insoluble, butwater-swellable polymers capable of absorbing aqueous liquids. Suchhydrogel-forming polymers are well known in the art and any of thesepolymers are useful in the present invention.

Hydrogel-forming absorbent polymers are also commonly referred to as“hydrocolloids,” or “absorbent” materials and can includepolysaccharides such as carboxymethyl starch, carboxymethyl cellulose,and hydroxypropyl cellulose; nonionic types such as polyvinyl alcohol,and polyvinyl ethers; cationic types such as polyvinyl pyridine,polyvinyl morpholinione, and N,N-dimethylaminoethyl orN,N-diethylaminopropyl acrylates and methaerylates, and the respectivequaternary salts thereof. Typically, hydrogel-forming absorbent polymersuseful in the present invention have a multiplicity of anionic orcationic functional groups such as sulfonic acid or amide or aminogroups, and more typically carboxy, groups. Examples of polymerssuitable for use herein include those that are prepared frompolymerizable, unsaturated, acid-containing monomers. Examples ofcationic polymers with cationic groups are prepared from base-containingmonomers. Thus, such monomers include the olefinically unsaturated acidsand anhydrides that contain at least one carbon-to-carbon olefinicdouble bond. More specifically, these monomers can be selected fromolefinically unsaturated carboxylic acids and acid anhydrides,olefinically unsaturated sulfonic acids, and mixtures thereof. Asindicated above, the nature of the hydrogel-forming absorbent polymer isnot critical to the present invention; nonetheless, the selection of theoptimal polymeric material may enhance the performance characteristicsof the present invention. The disclosure that follows describespreferred properties of the absorbent polymers useful herein. Theseproperties should not be interpreted as limitations; rather, they merelyindicate the progression that has occurred in the absorbent polymer artover the past several years.

Some non-acid monomers can also be included, usually in minor amounts,in preparing the hydrogel-forming absorbent polymers herein. Suchnon-acid monomers can include, for example, the water-soluble orwater-dispersible esters of the acid-containing monomers, as well asmonomers that contain no carboxylic or sulfonic acid groups at all.Optional non-acid monomers can thus include monomers containing thefollowing types of functional groups: carboxylic acid or sulfonic acidesters, hydroxyl groups, amide-groups, amino groups, nitrile groups,quaternary ammonium salt groups, aryl groups (e.g., phenyl groups, suchas those derived from styrene monomer). These non-acid monomers arewell-known materials and are described in greater detail, for example,in U.S. Pat. No. 4,076,663 (Masuda et al.), issued Feb. 28, 1978, and inU.S. Pat. No. 4,062,817 (Westerman), issued Dec. 13, 1977, both of whichare incorporated by reference.

Olefinically unsaturated carboxylic acid and carboxylic acid anhydridemonomers include the acrylic acids typified by acrylic acid itself,methacrylic acid, ethacrylic acid, α-chloroacrylic acid, a-cyanoacrylicacid, β-methylacrylic acid (crotonic acid), α-phenylacrylic acid,β-acryloxypropionic acid, sorbic acid, α-chlorosorbic acid, angelicacid, cinnamic acid, p-chlorocinnamic acid, β-sterylacrylic acid,itaconic acid, citroconic acid, mesaconic acid, glutaconic acid,aconitic acid, maleic acid, fumaric acid, tricarboxyethylene and maleicacid anhydride.

Olefinically unsaturated sulfonic acid monomers include aliphatic oraromatic vinyl sulfonic acids such as vinylsulfonic acid, allyl sulfonicacid, vinyl toluene sulfonic acid and styrene sulfonic acid; acrylic andmethacrylic sulfonic acid such as sulfoethyl acrylate, sulfoethylmethacrylate, sulfopropyl acrylate, sulfopropyl methacrylate,2-hydroxy-3-methacryloxypropyl sulfonic acid and2-acrylamide-2-methylpropane sulfonic acid.

Preferred hydrogel-forming absorbent polymers for use in the presentinvention contain carboxy groups. These polymers include hydrolyzedstarch-acrylonitrile graft copolymers, partially neutralized hydrolyzedstarch-acrylonitrile graft copolymers, starch-acrylic acid graftcopolymers, partially neutralized starch-acrylic acid graft copolymers,saponified vinyl acetate-acrylic ester copolymers, hydrolyzedacrylonitrile or acrylamide copolymers, slightly network crosslinkedpolymers of any of the foregoing copolymers, partially neutralizedpolyacrylic acid, and slightly network crosslinked polymers of partiallyneutralized polyacrylic acid. These polymers can be used either solelyor in the form of a mixture of two or more different polymers. Examplesof these polymer materials are disclosed in U.S. Pat. No. 3,661,875,U.S. Pat. No. 4,076,663, U.S. Pat. No. 4,093,776, U.S. Pat. No.4,666,983, and U.S. Pat. No. 4,734,478.

Most preferred polymer materials for use in making the hydrogel-formingabsorbent polymers are slightly network crosslinked polymers ofpartially neutralized polyacrylic acids and starch derivatives thereof.Most preferably, the hydrogel-forming absorbent polymers comprise fromabout 50 to about 95%, preferably about 75%, neutralized, slightlynetwork crosslinked, polyacrylic acid (i.e., poly (sodiumacrylate/acrylic acid)). Network crosslinking renders the polymersubstantially water-insoluble and, in part, determines the absorptivecapacity and extractable polymer content characteristics of thehydrogel-forming absorbent polymers. Processes for network crosslinkingthese polymers and typical network crosslinking agents are described ingreater detail in U.S. Pat. No. 4,076,663.

While the hydrogel-forming absorbent polymer is preferably of one type(i.e., homogeneous), mixtures of polymers can also be used in thepresent invention. For example, mixtures of starch-acrylic acid graftcopolymers and slightly network crosslinked polymers of partiallyneutralized polyacrylic acid can be used in the present invention.

The hydrogel-forming polymer component may also be in the form of amixed-bed ion-exchange composition comprising a cation-exchangehydrogel-forming absorbent polymer and an anion-exchangehydrogel-forming absorbent polymer. Such mixed-bed ion-exchangecompositions are described in, e.g., U.S. patent application Ser. No.09/130,321, filed Jan. 7, 1998 by Ashraf, et al. (P&G Case 6976R—titled“ABSORBENT POLYMER COMPOSITIONS WITH HIGH SORPTION CAPACITY AND HIGHFLUID PERMEABILITY UNDER AN APPLIED PRESSURE”); and U.S. Pat. No.6,121,509; the disclosure of each of which is incorporated herein byreference.

The hydrogel-forming absorbent polymers useful in the present inventioncan have a size, shape and/or morphology varying over a wide range.These polymers can be in the form of particles that do not have a largeratio of greatest dimension to smallest dimension (e.g., granules,pulverulents, interparticle aggregates, interparticle crosslinkedaggregates, and the like) and can be in the form of fibers, sheets,films, foams, flakes and the like. The hydrogel-forming absorbentpolymers can also comprise mixtures with low levels of one or moreadditives, such as for example powdered silica, zeolites, activatedcarbon, molecular sieves, surfactants, glue, binders, and the like. Thecomponents in this mixture can be physically and/or chemicallyassociated in a form such that the hydrogel-forming polymer componentand the non-hydrogel-forming polymer additive are not readily physicallyseparable.

The hydrogel-forming absorbent polymers can be essentially non-porous(i.e., no internal porosity) or have substantial internal porosity.

For particles as described above, particle size is defined as thedimension determined by sieve size analysis. Thus, for example, aparticle that is retained on a U.S.A. Standard Testing Sieve with 710micron openings (e.g., No. 25 U.S. Series Alternate Sieve Designation)is considered to have a size greater than 710 microns; a particle thatpasses through a sieve with 710 micron openings and is retained on asieve with 500 micron openings (e.g., No. 35 U.S. Series Alternate SieveDesignation) is considered to have a particle size between 500 and 710μm; and a particle that passes through a sieve with 500 micron openingsis considered to have a size less than 500 μm. The mass median particlesize of a given sample of hydrogel-forming absorbent polymer particlesis defined as the particle size that divides the sample in half on amass basis, i.e., one-half of the sample by weight will have a particlesize less than the mass median size and one-half of the sample will havea particle size greater than the mass median size. A standardparticle-size plotting method (wherein the cumulative weight percent ofthe particle sample retained on or passed through a given sieve sizeopening is plotted versus sieve size opening on probability paper) istypically used to determine mass median particle size when the 50% massvalue does not correspond to the size opening of a U.S.A. StandardTesting Sieve. These methods for determining particle sizes of thehydrogel-forming absorbent polymer particles are further described inU.S. Pat. No. 5,061,259 (Goldman et al.), issued Oct. 29, 1991, which isincorporated by reference.

For particles of hydrogel-forming absorbent polymers useful in thepresent invention, the particles will generally range in size from about1 to about 2000 μm, more preferably from about 20 to about 1000 μm. Themass median particle size will generally be from about 20 to about 1500μm, more preferably from about 50 μm to about 1000 μm, and even morepreferably from about 100 to about 800 μm. For embodiments containingfilms, membranes, foam, fibers, or polymers coated on a substrate like anonwoven, particles larger than the ones described above may be usefulor even preferred.

In specific embodiments, other properties of the absorbent polymer mayalso be relevant. In such embodiments, the materials may have one ormore of the properties described by U.S. Pat. No. 5,562,646, issued Oct.8, 1996 to Goldman et al. and U.S. Pat. No. 5,599,335, issued Feb. 4,1997 to Goldman et al., the disclosure of each of which is incorporatedby reference herein.

The basic hydrogel-forming absorbent polymer can be formed in anyconventional manner. Typical and preferred processes for producing thesepolymers are described in U.S. Reissue Pat. No. 32,649 (Brandt et al.),issued Apr. 19, 1988, U.S. Pat. No. 4,666,983 (Tsubakimoto et al.),issued May 19, 1987, and U.S. Pat. No. 4,625,001 (Tsubakimoto et al.),issued Nov. 25, 1986, all of which are incorporated by reference.

Preferred methods for forming the basic hydrogel-forming absorbentpolymer are those involving aqueous solution or other solutionpolymerization methods. As described in the above-referenced U.S. Pat.No. Reissue 32,649, aqueous solution polymerization involves the use ofan aqueous reaction mixture to carry out polymerization. The aqueousreaction mixture is then subjected to polymerization conditions that aresufficient to produce in the mixture, substantially water-insoluble,slightly network crosslinked polymer. The mass of polymer formed canthen be pulverized or chopped to form individual particles.

More specifically, the aqueous solution polymerization method forproducing the hydrogel-forming absorbent polymer comprises thepreparation of an aqueous reaction mixture in which to carry out thepolymerization. One element of such a reaction mixture is the acidgroup-containing monomer that will form the “backbone” of thehydrogel-forming absorbent polymer to be produced. The reaction mixturewill generally comprise about 100 parts by weight of the monomer.Another component of the aqueous reaction mixture comprises a networkcrosslinking agent. Network crosslinking agents useful in forming thehydrogel-forming absorbent polymer according to the present inventionare described in more detail in the above-referenced U.S. Reissue Pat.No. 32,649, U.S. Pat. No. 4,666,983, and U.S. Pat. No. 4,625,001. Thenetwork crosslinking agent will generally be present in the aqueousreaction mixture in an amount of from about 0.001 mole percent to about5 mole percent based on the total moles of monomer present in theaqueous mixture (about 0.01 to about 20 parts by weight, based on 100parts by weight of the monomer). An optional component of the aqueousreaction mixture comprises a free radical initiator including, forexample, peroxygen compounds such as sodium, potassium, and ammoniumpersulfates, caprylyl peroxide, benzoyl peroxide, hydrogen peroxide,cumene hydroperoxides, tertiary butyl diperphthalate, tertiary butylperbenzoate, sodium peracetate, sodium percarbonate, and the like. Otheroptional components of the aqueous reaction mixture comprise the variousnon-acidic co-monomers, including esters of the essential unsaturatedacidic functional group-containing monomers or other co-monomerscontaining no carboxylic or sulfonic acid functionalities.

The aqueous reaction mixture is subjected to polymerization conditionsthat are sufficient to produce in the mixture substantiallywater-insoluble, but water-swellable, hydrogel-forming absorbentslightly network crosslinked polymers. The polymerization conditions arealso discussed in more detail in the three above-referenced patents.Such polymerization conditions generally involve heating (thermalactivation techniques) to a polymerization temperature from about 0° toabout 100° C., more preferably from about 5° to about 40° C.Polymerization conditions under which the aqueous reaction mixture ismaintained can also include, for example, subjecting the reactionmixture, or portions thereof, to any conventional form of polymerizationactivating irradiation. Radioactive, electronic, ultraviolet, andelectromagnetic radiation are alternative conventional polymerizationtechniques.

The acid functional groups of the hydrogel-forming absorbent polymerformed in the aqueous reaction mixture are also preferably neutralized.Neutralization can be carried out in any conventional manner thatresults in at least about 25 mole percent, and more preferably at leastabout 50 mole percent, of the total monomer utilized to form the polymerbeing acid group-containing monomers that are neutralized with asalt-forming cation. Such salt-forming cations include, for example,alkali metals, ammonium, substituted ammonium and amines as discussed infurther detail in the above-references U.S. Reissue Pat. No. 32,649.

While it is preferred that the particulate versions of hydrogel-formingabsorbent polymer be manufactured using an aqueous solutionpolymerization process, it is also possible to carry out thepolymerization process using multi-phase polymerization processingtechniques such as inverse emulsion polymerization or inverse suspensionpolymerization procedures. In the inverse emulsion polymerization orinverse suspension polymerization procedures, the aqueous reactionmixture as described before is suspended in the form of tiny droplets ina matrix of a water-immiscible, inert organic solvent such ascyclohexane. The resultant particles of hydrogel-forming absorbentpolymer are generally spherical in shape. Inverse suspensionpolymerization procedures are described in greater detail in U.S. Pat.No. 4,340,706 (Obaysashi et al.), issued Jul. 20, 1982, U.S. Pat. No.4,506,052 (Flesher et al.), issued Mar. 19, 1985, and U.S. Pat. No.4,735,987 (Morita et al.), issued Apr. 5, 1988, all of which areincorporated by reference.

Surface crosslinking of the initially formed polymers is a preferredprocess for obtaining hydrogel-forming absorbent polymers havingrelatively high porosity hydrogel-layer (“PHL”), performance underpressure (“PUP”) capacity and saline flow conductivity (“SFC”) values,which may be beneficial in the context of the present invention.Suitable general methods for carrying out surface crosslinking ofhydrogel-forming absorbent polymers according to the present inventionare disclosed in U.S. Pat. No. 4,541,871 (Obayashi), issued Sep. 17,1985; published PCT application WO92/16565 (Stanley), published Oct. 1,1992, published PCT application WO90/08789 (Tai), published Aug. 9,1990; published PCT application WO93/05080 (Stanley), published Mar. 18,1993; U.S. Pat. No. 4,824,901 (Alexander), issued Apr. 25, 1989; U.S.Pat. No. 4,789,861 (Johnson), issued Jan. 17, 1989; U.S. Pat. No.4,587,308 (Makita), issued May 6, 1986; U.S. Pat. No. 4,734,478(Tsubakimoto), issued Mar. 29, 1988; U.S. Pat. No. 5,164,459 (Kimura etal.), issued Nov. 17, 1992; published German patent application4,020,780 (Dahmen), published Aug. 29, 1991; and published Europeanpatent application 509,708 (Gartner), published Oct. 21, 1992; all ofwhich are incorporated by reference. See also, U.S. Pat. No. 5,562,646(Goldman et al.), issued Oct. 8, 1996 and U.S. Pat. No. 5,599,335(Goldman et al.), issued Feb. 4, 1997, herein incorporated by reference.

For some embodiments of the present invention, it is advantageous if thehydrogel-forming absorbent polymer particles prepared according to thepresent invention are typically substantially dry. The term“substantially dry” is used herein to mean that the particles have aliquid content, typically water or other solution content, less thanabout 50%, preferably less than about 20%, more preferably less thanabout 10%, by weight of the particles. In general, the liquid content ofthe hydrogel-forming absorbent polymer particles is in the range of fromabout 0.01% to about 5% by weight of the particles. The individualparticles can be dried by any conventional method such as by heating.Alternatively, when the particles are formed using an aqueous reactionmixture, water can be removed from the reaction mixture by azeotropicdistillation. The polymer-containing aqueous reaction mixture can alsobe treated with a dewatering solvent such as methanol. Combinations ofthese drying procedures can also be used. The dewatered mass of polymercan then be chopped or pulverized to form substantially dry particles ofthe hydrogel-forming absorbent polymer.

Other Gelling Polymers

Gels based on acrylamide are also suitable for use in the presentinvention. Specifically suitable are acrylamide, 2-(acryloyloxyl)ethylacid phosphate, 2-acyrlamido-2-methylpropanesulfonic acid,2-dimethylaminoethyl acrylate, 2,2′-bis(acrylamido)acetic acid,3-(methacrylamido)propyltrimethylammonium chloride,acrylamidomethylpropanedimethylammonium chloride, acrylate,acrylonitrile, acrylic acid, diallyldimethylammonium chloride,diallylammonium chloride, dimethylaminoethyl acrylate,dimethylaminoethyl methacrylate, ethylene glycol, dimethacrylate,ethylene glycol monomethacrylate, methacrylamide,methylacrylamidopropyltrimethylammonium chloride,N,N-dimethylacrylamide,N-[2[[5-(dimethylamino)1-naphthaleny]sulfonyl]amino[ethyl]-2-acrylamide,N-[3-dimehtylamino)propyl]acrylamide hydrochloride,N-[3-(dimethylamino)propyl)methacrylamide hydrochloride,poly(diallyldimethylammonium chloride), sodium2-(2-carboxybenzoyloxy)ethyl methacrylate, sodium acrylate, sodium allylacetate, sodium methacrylate, sodium styrene sulfonate, sodiumvinylacetate, triallylamine, trimethyl(N-acryloyl-3-aminopropyl)ammoniumchloride, triphenylmethane-leuco derivatives, vinyl-terminatedpolymethylsiloxane, N-(2-ethoxyethyl)acrylamide,N-3-(methoxypropyl)acrylamide, N-(3-ethoxypropyl)acrylamide,N-cyclopropylacrylamide, N-n-propylacrylamide, andN-(tetrahydrofurfuryl)acrylamide.

Also suitable are the gels based on N-isopropylacrylamide. These caninclude N-isopropylacrylamide, 2-(diethylamino)ethyl methacrylate,2-(dimethylamino)ethyl methacrylate,2-acrylamido-2-methyl-1-propanesulfonacrylate, acrylic acid, acrylamidealkyl methacrylate, bis(4-dimethylamino)phenyl)(4-vinylphenyl)methylleucocyanide, Concanavalin A (Lecithin), hexyl methacrylate, laurylmethacrylate, methacrylic acid, methacrylamidopropyltrimethylammoniumchloride, n-butyl methacrylate, poly(tetrafluoroethylene),polytetramethylene ether glycol, sodium acrylate, sodium methacrylate,sodium vinyl sulfonate, and vinyl-terminated polymethylsiloxane.

Also suitable are the gels based on N,N′-diethylacrylamide. These caninclude N,N′-diethylacrylamide, methyacrylamidopropyltrimethylammoniumchloride, N-acryloxysuccinimide ester, N-tert-butylacrylamide, andsodium methacrylate.

Gels based on acrylate are also suitable. These may include2-dimethylaminoethyl acrylate, 2-acrylamido-2-methylpropanesulfonicacid, acrylamide, triallylamine, acrylate, acrylamide, methylmethacrylate, divinylbenzene, N,N-dimehtylaminoethyl methacrylate,poly(oxytetramethylene dimethacrylate), poly(2-hydroxyethylmethacrylate), poly(2-hydroxypropyl methacrylate), and polyethyleneglycol methacrylate.

Also suitable are the gels based on various monomers. These can includeacrylic acid, methacrylamidopropyltrimethylammonium chloride, Collagen,dipalmitoylphosphatidylethanolamine,poly[4-6-decadiene-1,10-diolbis(n-butoxycarbonylmethyl urethane)],poly[bis[aminoethoxy)ethoxy]phosphazene],poly[bis[(butoxyethoxy)ethoxy]phosphazene],poly[bis[ethoxyethoxy)ethoxy]phosphazene],poly[bis[methoxyethoxy)ethoxy]phosphazene],poly[bis[methoxyethoxy)phosphazene], polydimethylsiloxane, polyethyleneoxide, poly(ethylene-dimethylsiloxane-ethylene oxide),poly(N-acrylopyrrolidine),poly[n,n-dimethyl-N-[(methacryloyloxyethyl]-N-(3-sulfopropyl)ammoniumbetaine], polymethacrylic acid, polymethacryloyl dipeptide, polyvinylalcohol, polyvinyl alcohol-vinyl acetate, polyvinyl methyl ether,furan-modified poly(n-acetylethylene imine), and malein imide-modifiedpoly(n-acetylethylene imine).

Also suitable as hydrogels are hydrogels that comprise a monomerselected from the group consisting of: include hydroxyalkyl acrylates,hydroxyalkyl methacrylates, N-substituted acrylamides, N-substitutedmethacrylamides, N-vinyl-2-pyrrolidone, N-acroylpyrrolidone, acrylics,methacrylics, vinyl acetate, acrylonitrile, styrene, acrylic acid,methacrylic acid, crotonic acid, sodium styrene sulfonate, sodium2-sulfoxyethyl methacrylate, 2-acrylamido-2-methylpropanesulfonic acid,vinylpyridine, aminoethyl methacrylates,2-methacryloyloxytrimethylammonium chloride,N,N′-methylenebisacrylamide, poly(ethylene glycol) dimethacrylate,2,2′-(p-phenylenedioxy diethyl dimethacrylate, divinylbenzene andtriallylamine.

Also suitable are the gels disclosed in U.S. Pat. Nos. 4,555,344,4,828,710, and European Application EP 648,521 A2 (all of which areherein incorporated by reference).

High Surface Area Materials

In addition to the osmotic absorbent (for example, hydrogel-formingabsorbent polymers), the present invention can comprise a high surfacearea material. It is this high surface area material that provides,either itself or in combination with the hydrogel-forming absorbentpolymer, the separation apparatus or vessel with high capillary sorptionabsorbent capacity. As discussed herein, high surface area materials aredescribed, in one regard, in terms of their capillary sorption absorbentcapacity (measured without hydrogel-forming polymer or any otheroptional material contained in the separation apparatus or vessel). Itis recognized that materials having high surface areas may have uptakecapacities at very high suction heights (e.g., 100 cm or higher). Thisallows the high surface area materials to provide one or both of thefollowing functions: i) a capillary pathway of liquid to the osmoticabsorbents, and/or ii) additional absorbent capacity. Thus, while thehigh surface area materials may be described in terms of their surfacearea per weight or volume, applicants herein alternatively use capillarysorption absorbent capacity to describe the high surface area materialbecause capillary sorption absorbent capacity is a performance parameterthat generally will provide the separation apparatus or vessel used inthe present invention with the requisite suction capabilities to provideimproved absorbent articles. It will be recognized that certain highsurface area materials, e.g. glass microfibers, will themselves notexhibit particularly high capillary sorption absorbent capacity at allheights, especially very high heights (e.g., 100 cm and higher).Nonetheless, such materials may provide the desired capillary pathway ofliquid to the hydrogel-forming absorbent polymer or other osmoticabsorbent to provide the requisite capillary sorption absorbentcapacities, even at relatively high heights, when combined with thehydrogel-forming polymer or other osmotic absorbent.

Any material having sufficient capillary sorption absorbent capacitywhen used in combination with the hydrogel-forming absorbent polymer orother osmotic absorbent will be useful in the separation apparatus orvessel of the present invention. In this regard, the term “high surfacearea material” refers to any material that itself (i.e., as measuredwithout the osmotic absorbent or any other optional material that iscontained in the separation apparatus or vessel) exhibits one or more ofthe following capillary sorption absorbent capacities: (I) A capillarysorption absorbent capacity of at least about 2 g/g at a suction heightof 100 cm, preferably at least about 3 g/g, still more preferably atleast about 4 g/g, and still more preferably at least about 6 g/g, at aheight of 100 cm; (II) A capillary sorption absorbent capacity at aheight of 35 cm of at least about 5 g/g, preferably at least about 8g/g, more preferably at least about 12 g/g; (III) A capillary sorptionabsorbent capacity at a height of 50 cm of at least about 4 g/g,preferably at least about 7 g/g, more preferably at least about 9 g/g;(IV) A capillary sorption absorbent capacity at a height of 140 cm of atleast about 1 g/g, preferably at least about 2 g/g, more preferably atleast about 3 g/g, still more preferably at least about 5 g/g; or (V) Acapillary sorption absorbent capacity at a height of 200 cm of at leastabout 1 g/g, preferably at least about 2 g/g, more preferably at leastabout 3 g/g, still more preferably at least about 5 g/g.

In one embodiment, the high surface area material will be fibrous(hereafter referred to as “high surface area fibers”) in character, soas to provide a fibrous web or fibrous matrix when combined with thehydrogel-forming absorbent polymer or other osmotic absorbent.Alternatively, the high surface area material will be an open-celled,hydrophilic polymeric foam (hereafter referred to as “high surface areapolymeric foams” or more generally as “polymeric foams”). Thesematerials are described in detail below.

High surface area fibers useful in the present invention include thosethat are naturally occurring (modified or unmodified), as well assynthetically made fibers. The high surface area fibers have surfaceareas much greater than fibers typically used in absorbent articles,such as wood pulp fibers. The high surface area fibers used in thepresent invention will desirably be hydrophilic. As used herein, theterm “hydrophilic” describes fibers, or surfaces of fibers, that arewettable by aqueous liquids (e.g., aqueous body liquids) deposited onthese fibers. Hydrophilicity and wettability are typically defined interms of contact angle and the surface tension of the liquids and solidsinvolved. This is discussed in detail in the American Chemical Societypublication entitled Contact Angle, Wettability and Adhesion, edited byRobert F. Gould (Copyright 1964). A fiber, or surface of a fiber, issaid to be wetted by a liquid (i.e., hydrophilic) when either thecontact angle between the liquid and the fiber, or its surface, is lessthan 90 degrees, or when the liquid tends to spread spontaneously acrossthe surface of the fiber, both conditions normally co-existing.Conversely, a fiber or surface is considered to be hydrophobic if thecontact angle is greater than 90 degrees and the liquid does not spreadspontaneously across the surface of the fiber. The hydrophilic characterof the fibers useful herein may be inherent in the fibers, or the fibersmay be naturally hydrophobic fibers that are treated to render themhydrophilic. Materials and methods for providing hydrophilic characterto naturally hydrophobic fibers are well known.

High surface area fibers useful herein will have capillary suctionspecific surface areas in the same range as the polymeric foamsdescribed below. Typically, however, high surface area fibers arecharacterized in terms of BET surface area.

High surface area fibers useful herein include glass microfibers suchas, for example, glass wool available from Evanite Fiber Corp.(Corvallis, Oreg.). Glass microfibers useful herein will typically havefiber diameters of not more than about 0.8 μm, more typically from about0.1 μm to about 0.7 μm. These microfibers will have surface areas of atleast about 2 m²/g, preferably at least about 3 m²/g. Typically, thesurface area of glass microfibers will be from about 2 m²/g to about 15m²/g. Representative glass microfibers for use herein are thoseavailable from Evanite Fiber Corp. as type 104 glass fibers, which havea nominal fiber diameter of about 0.5 μm. These glass microfibers have acalculated surface area of about 3.1 m²/g.

Another type of high surface area fibers useful herein are fibrillatedcellulose acetate fibers. These fibers (referred to herein as “fibrets”)have high surface areas relative to cellulose-derived fibers commonlyemployed in the absorbent article art. Such fibrets have regions of verysmall diameters, such that their particle size width is typically fromabout 0.5 to about 5 μm. These fibrets typically have a surface area ofabout 20 m²/g. Representative fibrets useful as the high surface areamaterials herein are available from Hoechst Celanese Corp. (Charlotte,N.C.) as cellulose acetate Fibrets®. For a detailed discussion offibrets, including their physical properties and methods for theirpreparation, see “Cellulose Acetate Fibrets: A Fibrillated Pulp WithHigh Surface Area”, Smith, J. E., Tappi Journal, December 1988, p. 237;and U.S. Pat. No. 5,486,410 (Groeger et al.) issued Jan. 23, 1996; thedisclosure of each of which is incorporated by reference herein.

In addition to these fibers, the skilled artisan will recognize thatother fibers well known in the absorbency art may be modified to providehigh surface area fibers for use herein. Representative fibers that maybe modified to achieve high surface areas required by the presentinvention are disclosed in U.S. Pat. No. 5,599,335, supra (seeespecially columns 21-24), incorporated herein by reference.

Regardless of the nature of the high surface area fibers utilized, thefibers and the osmotic absorbent will be discrete materials prior tocombination. As used herein, the term “discrete” means that the highsurface area fibers and the osmotic absorbents are each formed prior tobeing combined to form the core of the separation apparatus or vessel.In other words, the high surface area fibers are not formed subsequentto mixing with the osmotic absorbent (e.g., hydrogel-forming absorbentpolymer), nor is the osmotic absorbent formed after combination with thehigh surface area fibers. Combining of the discrete respectivecomponents ensures that the high surface area fibers will have thedesired morphology and, more importantly, the desired surface area.

Spacers

Spacer materials may be used in the absorbent materials of the presentinvention. Spacer materials suitable for use in the present inventioninclude any fibrous or particulate material that is, at most, onlyslightly soluble in water and/or lipophilic fluid. The spacer can bedispersed throughout a matrix of absorbent material in order to improveits permeability above that of a matrix made up of an absorbent materialalone; or, the spacer can be used to maintain permeability even afterthe absorbent material swells and/or gels upon exposure to water.Therefore, the spacer helps reduce the pressure drop across an absorbentmaterial matrix when a water-bearing fluid is passed through the matrix.In addition, if the absorbent material is prone to congealing afterexposure to water and subsequent collapse, the spacer can aid in thereduction or prevention of gel congealing upon collapse.

Non-limiting examples of suitable spacer materials include sand, silica,aluminosilicates, glass microspheres, clay, layered silicates, wood,natural textile materials, synthetic textile materials, alumina,aluminum oxide, aluminum silicate, zinc oxide, molecular sieves,zeolites, activated carbon, diatomaceous earth, hydrated silica, mica,microcrystalline cellulose, montmorillonite, peach pit powder, pecanshell powder, talc, tin oxide, titanium dioxide, walnut shell powder,and particles of different metals or metal alloys. Also useful areparticles made from mixed polymers (e.g., copolymers, terpolymers,etc.), such as polyethylene/polypropylene copolymer,polyethylene/propylene/isobutylene copolymer, polyethylene/styrenecopolymer, and the like.

Other particulate materials useful herein are the synthetic polymericparticles selected from the group consisting of polybutylene,polyethylene, polyisobutylene, polymethylstyrene, polypropylene,polystyrene, polyurethane, nylon, teflon, and mixtures thereof. Ofthese, the most preferred are polyethylene and polypropylene particles,with the oxidized versions of these materials being especiallypreferred. Examples of commercially available particles useful hereininclude the ACumist™ micronized polyethylene waxes available from AlliedSignal (Morristown, N.J.) available as the A, B, C, and D series in avariety of average particle sizes ranging from 5 microns to 60 microns.Preferred are the ACumist™ A-25, A-30, and A-45 oxidized polyethyleneparticles having a means particle size of 25, 30, and 45 microns,respectively. Examples of commercially available polypropylene particlesinclude the Propyltex series available from Micro Powders (Dartek) andACuscrub™ 51, available from Allied Signal (Morristown, N.J.) having amean particle size of about 125 microns.

Absorbent Matrix

In order to increase the “dry” absorbent matrix permeability or maintainthe permeability of the absorbent matrix when it is wet, it is importantto provide a sufficient absorbent material to spacer, and, optionally,high surface area material ratio. Since the weight of possible spacerscan vary greatly with respect to the weight of the absorbent material,the proportion must be quantified on a “dry” volumetric basis. “Netmatrix volume” is the volume of the absorbent materials, spacers, and,optionally, any high surface area materials not including anyinter-material volume the materials themselves may contain or any volumeattributable to intra-material void spaces. “Intra-material void volume”is the cumulative volume of voids between material particles and/orfibers that typically and naturally occurs when particles and/or fibersoccupy a given space. “Dry bulk matrix volume” is equal to the netmatrix volume combined with the intra-material void volume on a drybasis. With respect to the present invention, it is preferred that theabsorbent material is from 50 to 100%, more preferably from 75 to 95%,of the dry bulk matrix volume. It is preferred that the spacer is from 1to 50%, more preferably from 5 to 25%, of the dry bulk matrix volume. Itis preferred that the optional high surface area material be from 1 to50%, more preferably from 5 to 25%, of the dry bulk matrix volume.

The gel materials, spacers, and, optionally, the high surface areamaterials can be formed into fibrous structures, woven or non-woven,such as sheets or films or membranes and configured in different ways.The sheet configuration is application-dependent and generally includesfour generic configurations, namely, tubes, hollow fibers, plate andframe units, and spiral wound modules, all of which are within the scopeof the present invention.

The loading density of water absorbing agent on such fibrous structuresof the present invention may be in the range of from about 50 g ofagent/m2 of fibrous structure to about 2000 g of agent/m2 of fibrousstructure.

Tubes are, perhaps, the simplest configuration, in which the sheet iscast on the inside wall of a porous support tube. The tubeconfiguration, however, can be cost-prohibitive with the porous supporttube itself being the dominant cost factor.

Hollow fibers are, in theory, the ideal sheet configuration in thatthere is no “parasite” drag and no expensive porous support tube. Suchfibers can be pressurized on the inside permitting “thin channel” fluidmanagement of the water-bearing fluid. However, the biggest disadvantageof hollow fibers is the pressure constraint, which limits the cross-flowvelocity down the lumen of the fiber. In addition, the hollow fiberconfiguration is more susceptible to fouling and plugging than the otherthree configurations; however, larger diameter fibers are becomingpopular to improve fouling resistance. Fortunately, hollow fibers can bereadily cleaned by back washing, which tends to compensate for theirpropensity to foul. In contrast, it is not recommended that tubes; plateand frame units; and spiral wound modules be back-washed, due toproblems with membrane delamination and glue line seal rupture.

Flat sheets in a plate and frame unit offer the greatest versatility;they are also the most cost-prohibitive.

While spiral wound modules were originally developed for reverseosmosis; they are capturing an increased share of the ultrafiltrationmarket by providing one of the least expensive ultrafiltration modulesavailable in terms of cost per sheet area unit. Spiral wound unitscannot be unwrapped for cleaning and most cannot be autoclaved. In termsof propensity to fouling, they are between hollow fibers and tubes (aswell as the pricier plate and frame units).

The gel material can also be directly deposited onto a fibrous structureor a spacer material. This can be achieved by first applying the aqueoussolution of a monomer containing from 10 to 100% of a water-solubleunsaturated monomer onto a fibrous structure or a spacer material andthen polymerizing said monomer.

The thickness of the fibrous structure is generally in the range of from0.01 to 10 mm, preferably 0.1 to 5 mm. The non-woven fabric is desiredto have a basis weight in the range of from 5 to 1000 g/sq. m,preferably from 10 to 300 g/sq. m.

Processes of the Invention

The present invention is directed to a process for removing water from alipophilic fluid and water emulsion. The process includes exposing theemulsion to an absorbent material, as discussed in detail above, inorder to effect the removal of the water from the lipophilic fluid andwater emulsion. The lipophilic fluid is recovered and termed “lipophilicfluid.” Within this process, it is possible to add the optional initialsteps of exposing a fabric to lipophilic fluid and water and thenrecovering the lipophilic fluid and water in the form of the lipophilicfluid and water emulsion.

Although not required, it is also possible to pass the lipophilic fluidand water emulsion through a particulate matter filter such thatparticles and particle aggregates about 1 micron or larger are removed,preferably such that particles and particle aggregates about 5 micronsor larger are removed, more preferably such that particles and particleaggregates about 10 microns or larger are removed, even more preferablysuch that particles and particle aggregates about 15 microns or largerare removed, even more preferably such that particles and particleaggregates about 25 microns or larger are removed. It is furtherpossible to add to the process the step of exposing the lipophilic fluidand water emulsion to activated carbon prior to exposure to theabsorbent material.

As previously discussed, the absorbent material may comprise surfacecross-linked polymers, surface cross-linked polyacrylates, surfacecross-linked polyacrylamides, or combinations of these absorbentmaterials. Further, any of the absorbent materials may have a fibrousmorphology, a particulate morphology, or mixtures of any of theabsorbent materials with similar or different morphologies. Theabsorbent material may take several forms, including but not limited to,a porous woven sheet impregnated with absorbent materials, a film, or amembrane.

In order to aid the absorption of water from and/or separation of thelipophilic fluid and water emulsion, it may be desirable to increase thetemperature of the emulsion prior to exposing the emulsion to theabsorbent material. If the emulsion is preheated, it is preferable toheat it by at least about 10° C. Preferably however, the temperature ofthe lipophilic fluid and water emulsion is at most about 50° C. prior toexposing the emulsion to absorbent material since some absorbentmaterials cannot absorb water at higher temperatures, particularly whentemperature increase is one of their trigger or collapse mechanisms.Aside from heating the emulsion in order to aid the absorption of waterfrom and/or separation of the lipophilic fluid and water emulsion, itmay be additionally or alternatively desirable to cool the emulsion,and/or add demulsifying agents to the emulsion in order to aid theabsorption of water from and/or separation of the lipophilic fluid andwater emulsion.

Once the absorbent material has absorbed at least a portion of the waterremoved from the lipophilic fluid and water emulsion, it is desirable totrigger the absorbent material to release the removed water by exposingthe absorbent material to a trigger mechanism including, but not limitedto, light, pH, temperature, sound, electric field, pressure, ionicstrength, vibration, and combinations of these trigger mechanisms.Absorbent material “trigger” or “collapse” mechanisms and methods fortheir introduction are well known in the absorbent material arts.

Once the emulsion is separated, the collected lipophilic fluid can beexposed to activated carbon in order to further facilitate itspurification and recycling into the system. Further, the removed watermay also be exposed to activated carbon prior to its disposal orrecycling into the system. Methods to purify the collected or separatedlipophilic fluid include well-known distillation processes, membranefilters, adsorption processes, absorption processes, extractionprocesses, ion exchange processes, air stripping processes, andchromatography.

The lipophilic fluid and water emulsion may also contain up to about 10%emulsifier by weight of the emulsion. If it does contain emulsifier, itis preferable for the lipophilic fluid and water emulsion to have awater/lipophilic fluid/emulsifier ratio of from about 1/98.9/0.1 toabout 40/55/5 by weight of the emulsion. Further, as discussed in the“Adjunct Ingredients” section above, it is preferred that the emulsifieralso contains a surfactant. Lastly, also as discussed in theaforementioned section, the lipophilic fluid and water emulsion may alsocontain adjunct ingredients selected from the group consisting ofenzymes, bleaches, surfactants, fabric softeners, perfumes,antibacterial agents, antistatic agents, brighteners, dye fixatives, dyeabrasion inhibitors, anti-crocking agents, wrinkle reduction agents,wrinkle resistance agents, soil release polymers, sunscreen agents,anti-fade agents, builders, sudsing agents, composition malodor controlagents, composition coloring agents, pH buffers, waterproofing agents,soil repellency agents, and mixtures of these adjuncts.

In the present invention, it is preferred that the lipophilic fluidincludes a linear siloxane, a cyclic siloxane, and mixtures of thesesiloxanes. It is more preferable that these siloxanes are selected fromthe group consisting of octamethylcyclotetrasiloxane,decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, andmixtures of these siloxanes. It is even more preferred if the lipophilicfluid contains decamethylcyclopentasiloxane. Lastly, it is mostpreferred if the lipophilic fluid contains decamethylcyclopentasiloxaneand is substantially free of octamethylcyclotetrasiloxane.

It was also surprisingly found that absorbent materials such as gels caneffectively remove surfactants from the lipophilic fluid and wateremulsion. The surfactant that are removed may include the followingnonlimiting examples:

-   a) Anionic surfactants (e.g., alkyl or aryl sulfates, aerosol    derivatives, etc)-   b) Cationic or basic surfactants (e.g., quaternary surfactants,    primary and secondary amines, etc.)    -   Or combinations of above.        Systems of the Invention

The present invention also includes a system for removing water from alipophilic fluid and water emulsion. In addition to the followingdisclosure, the system can be capable of performing the previouslydescribed method including non-essential and preferredmethods/limitations/modes of operation. Mainly, the system is capable ofexposing an emulsion of a lipophilic fluid and water and/or surfactantto an absorbent material in order to effect the removal of water and/orsurfactant from the emulsion wherein at least the lipophilic fluid isrecovered from the absorbent material as pure or substantially purelipophilic fluid. As in the method, the system may be additionallycapable of initially exposing a fabric to a lipophilic fluid and waterand/or surfactants and recovering the lipophilic fluid and water and/orsurfactants in the form of an emulsion of a lipophilic fluid and waterand/or surfactants. The system may additionally be capable of passingthe emulsion of a lipophilic fluid and water and/or surfactants througha particulate matter filter such that particles and particle aggregatesabout 1 micron or larger are removed. As with the previously describedmethod, the absorbent material may take the form of a porous woven sheetimpregnated with absorbent polymers.

The methods and systems of the present invention may be used in aservice, such as a dry cleaning service, diaper service, uniformcleaning service, or commercial business, such as a Laundromat, drycleaner, linen service which is part of a hotel, restaurant, conventioncenter, airport, cruise ship, port facility, casino, or may be used inthe home.

The methods of the present invention may be performed in an apparatusthat is a modified existing apparatus and is retrofitted in such amanner as to conduct the process of the present invention in addition torelated processes.

The methods of the present invention may also be performed in anapparatus, which is not a modified existing apparatus but is onespecifically built in such a manner so as to conduct the presentinvention or may be added to another apparatus as part of a lipophilicfluid processing system. This would include all the associated plumbing,such as connection to a chemical and water supply, and sewerage forwaste wash fluids.

The systems of the present invention may be used in an apparatus, whichis not a modified existing apparatus but is one specifically built insuch a manner so as to conduct the present invention and relatedprocesses.

The methods of the present invention may also be performed in anapparatus capable of “dual mode” functions. A “dual mode” apparatus isone capable of both washing and drying fabrics within the same drum.These apparati are commercially available, particularly in Europe.

An apparatus used to carry out the present invention will typicallycontain some type of control system. These include electrical systems,such as, the so-called smart control systems, as well as moretraditional electromechanical systems. The control systems would enablethe user to select the size of the fabric load to be cleaned, the typeof soiling, the extent of the soiling, the time for the cleaning cycle.Alternatively, the user could use pre-set cleaning and/or refreshingcycles, or the apparatus could control the length of the cycle, based onany number of ascertainable parameters. This would be especially truefor electrical control systems. For example, when the collection rate oflipophilic fluid reaches a steady rate the apparatus could turn its selfoff after a fixed period of time, or initiate another process for thelipophilic fluid.

In the case of electrical control systems, one option is to make thecontrol device a so-called “smart device”. This could mean including,but not limited to, self diagnostic system, load type and cycleselection, linking the machine to the Internet and allowing for theconsumer to start the apparatus remotely, be informed when the apparatushas cleaned a fabric article, or for the supplier to remotely diagnoseproblems if the apparatus should break down. Furthermore, if the systemof the present invention is only a part of a cleaning system, the socalled “smart system” could be communicating with the other cleaningdevices which would be used to complete the remainder of the cleaningprocess, such as a washing machine, and a dryer.

The emulsion de-watering filter 70 (see FIG. 1) contains a outercylinder 30 sealed from both ends by discs 27 and 28. The disc 27 has aninlet opening 25 that accesses the inside of the outer cylinder 30. Thedisc 28 has an opening 26 that establishes communication with perforatedinner cylinder 35. Emulsion de-watering media 40 forms a barrier betweenthe inside of outer cylinder 30 and inner cylinder 35. The emulsionde-watering media 40 consists of a fiber material used to supportsuperabsorbent polymer particles. Gel particles are uniformlydistributed through the fiber material.

The further process steps may include:

-   -   a) Pumping lipophilic fluid emulsion thru the inlet 27 inside        the outer cylinder 30 and contacting lipophilic fluid emulsion        with emulsion de-watering media 40.    -   b) Removing de-watered lipophilic fluid with reduced surfactant        content thru perforations of inner tube 35 and outlet 28.

In the new development, fiber material is used to provide a supportstructure for polymer particles and provide sufficient void spacebetween polymer particles. The void space allows particles to swell uponexposure to water without restricting the flow of the emulsion.

The emulsion of the lipophilic fluid and water may pass through thewater absorbing agent housed within the housing of the filter from theinlet to the outlet at a flow rate of from about 10 ml/min to about 1000ml/min.

In one embodiment, the filter comprises a filter housing, an inlet port,an outlet port, and a water absorbing agent housed within the housing;the distribution of the water absorbing agent within the housing isgreater nearer the outlet port than the inlet port.

It was also discovered that contacting a lipophilic fluid emulsioncontaining surfactants with ionic gels resulted in increase of dryweight of gels. The increase in dry weight of gels corresponded to asignificant amount of surfactants being absorbed into the ionic gelstructure. Moreover, even though significant amounts of surfactant areabsorbed into the gel, the gel water absorbing capacity remains thesame. Therefore, an additional benefit of gels to remove surfactants isutilized without reducing the gel water absorbing performance.

1. A filter system for removing water from a lipophilic fluidcomprising: a. a filter housing; b. an inlet port in the housing forreceiving a lipophilic fluid and water emulsion comprising a lipophilicfluid and water, and optionally, a surfactant; c. an outlet port in thehousing for releasing a pure or substantially pure lipophilic fluid; d.a quantity of water absorbing agent having a water absorbing capacity ofat least about 50 g of water/g of water absorbing agent, the waterabsorbing agent is housed within the housing; and e. a source of thelipophilic fluid and water emulsion in fluid communication with thewater absorbing agent through the inlet port; wherein the lipophilicfluid is selected from the group consisting of linear or cyclicsiloxanes, perflourinated amines, C6 or higher diols, polyol esters, andmixtures thereof; and distribution of the water absorbing agent withinthe housing is greater nearer the outlet port than the inlet port. 2.The filter system according to claim 1 wherein the water absorbing agenthas an average particle size of from about 5 microns to about 500microns.
 3. The filter system according to claim 1 wherein the waterabsorbing agent is selected from the group consisting of hydrogelagents, actylate-containing agents, acrylamide-containing agents,cellulose-containing agents and mixtures thereof.
 4. The filter systemaccording to claim 1 wherein the water absorbing agent comprises two ormore agents each separate and discrete from the other agents.
 5. Thefilter system according to claim 1 wherein the water absorbing agentcomprises two or more agents commingled.
 6. The filter system accordingto claim 1 wherein the filter system comprises a fibrous structure. 7.The filter system according to claim 6 wherein the fibrous structure isin the form of a sheet.
 8. The filter system according to claim 6wherein the water absorbing agent is loaded onto the fibrous structureand loading density of water absorbing agent is in the range of fromabout 50 to about 2000 g of agent/m² of fibrous structure.
 9. The filtersystem according to claim 6 wherein the fibrous structure is a non-wovenfibrous structure.
 10. The filter system according to claim 1 whereinthe filter system has a flow rate of from about 10 ml/mm to about 1000ml/min.
 11. The filter system according to claim 1 wherein water isremoved from the lipophilic fluid and water emulsion to a level of lessthan 5 ppm of water in the pure or substantially pure lipophilic fluid.12. The filter system according to claim 1 wherein the absorbing agentfurther comprises a surfactant-removing agent.
 13. A process forremoving water and/or surfactant from a lipophilic fluid comprisingcontacting the filter system according to claim 12 with the lipophilicfluid and water emulsion such that water and optionally also surfactantare removed from the lipophilic fluid.